Insights into the In Vivo Regulation of Glutamate Dehydrogenase from the Foot Muscle of an Estivating Land Snail

Table 5

The effect of various metabolites on purified foot muscle GDH activity from control and 10 day estivated Otala lactea. GDH was assayed in the glutamate-synthesizing direction. 𝐾_𝑎 and 𝐼₅₀ values were determined at suboptimal substrate concentrations (defined in the Section 2). Data are means ± SEM, 𝑛≥3 independent purified preparations. *Significantly different from the corresponding control value using the Student’s 𝑡-test, 𝑃<0.05.

	Control	10-day estivated
𝐾𝑎 AMP (mM)	0.27±0.04	No Effect (up to 4.5 mM)
𝐼50 ATP (mM)	7±1	No Effect (up to 10 mM)
𝐼50 GTP (μM)	0.34±0.02	0.15±0.02 *
Citrate	No Effect	No Effect